108 lines · cpp
1//===----------------------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9// UNSUPPORTED: !stdlib=libc++ && (c++03 || c++11 || c++14)10 11// <string_view>12 13// constexpr const_iterator rend() const;14 15#include <string_view>16#include <cassert>17#include <cstddef>18 19#include "test_macros.h"20 21template <class S>22void test(S s) {23 const S& cs = s;24 typename S::reverse_iterator e = s.rend();25 typename S::const_reverse_iterator ce1 = cs.rend();26 typename S::const_reverse_iterator ce2 = s.crend();27 28 if (s.empty()) {29 assert(e == s.rbegin());30 assert(ce1 == cs.rbegin());31 assert(ce2 == s.rbegin());32 } else {33 assert(e != s.rbegin());34 assert(ce1 != cs.rbegin());35 assert(ce2 != s.rbegin());36 }37 38 assert(static_cast<std::size_t>(e - s.rbegin()) == s.size());39 assert(static_cast<std::size_t>(ce1 - cs.rbegin()) == cs.size());40 assert(static_cast<std::size_t>(ce2 - s.crbegin()) == s.size());41 42 assert(e == ce1);43 assert(e == ce2);44 assert(ce1 == ce2);45}46 47int main(int, char**) {48 typedef std::string_view string_view;49#ifndef TEST_HAS_NO_CHAR8_T50 typedef std::u8string_view u8string_view;51#endif52 typedef std::u16string_view u16string_view;53 typedef std::u32string_view u32string_view;54 55 test(string_view());56 test(u16string_view());57 test(u32string_view());58 test(string_view("123"));59#ifndef TEST_HAS_NO_CHAR8_T60 test(u8string_view{u8"123"});61#endif62#if TEST_STD_VER >= 1163 test(u16string_view{u"123"});64 test(u32string_view{U"123"});65#endif66 67#ifndef TEST_HAS_NO_WIDE_CHARACTERS68 typedef std::wstring_view wstring_view;69 test(wstring_view());70 test(wstring_view(L"123"));71#endif72 73#if TEST_STD_VER > 1474 {75 constexpr string_view sv{"123", 3};76# ifndef TEST_HAS_NO_CHAR8_T77 constexpr u8string_view u8sv{u8"123", 3};78# endif79 constexpr u16string_view u16sv{u"123", 3};80 constexpr u32string_view u32sv{U"123", 3};81 82 static_assert(*--sv.rend() == sv[0], "");83# ifndef TEST_HAS_NO_CHAR8_T84 static_assert(*--u8sv.rend() == u8sv[0], "");85# endif86 static_assert(*--u16sv.rend() == u16sv[0], "");87 static_assert(*--u32sv.rend() == u32sv[0], "");88 89 static_assert(*--sv.crend() == sv[0], "");90# ifndef TEST_HAS_NO_CHAR8_T91 static_assert(*--u8sv.crend() == u8sv[0], "");92# endif93 static_assert(*--u16sv.crend() == u16sv[0], "");94 static_assert(*--u32sv.crend() == u32sv[0], "");95 96# ifndef TEST_HAS_NO_WIDE_CHARACTERS97 {98 constexpr wstring_view wsv{L"123", 3};99 static_assert(*--wsv.rend() == wsv[0], "");100 static_assert(*--wsv.crend() == wsv[0], "");101 }102# endif103 }104#endif // TEST_STD_VER > 14105 106 return 0;107}108